半焦负载钙和铁催化还原NO的研究

用浸渍法制备负载Ca和Fe的褐煤半焦,采用程序升温和恒温法在石英固定床反应器上于常压反应条件下研究了NO-半焦催化还原反应.研究发现,Ca和Fe对半焦还原NO的反应具有催化作用,其中Fe的催化作用强于Ca;热处理温度升高,Ca的催化作用降低,但热处理温度的变化基本不影响Fe的催化活性;CO和O₂气氛可以促进NO的还原,温度升高CO和O₂的促进作用减小.

Catalytic Reduction of NO by Chars Loaded with Ca and Fe

The effects of calcium and iron impregnated on coal chars as catalysts in NO char reaction were investigated. The NO char reaction was studied in a quartz fixed bed reactor at atmospheric pressure. Temperature programmed reaction (TPR) and isothermal reaction were used to determine the catalytic activities of calcium and iron at various atmosphere environments. The results showed that the higher the temperatures of pretreatment, the lower the catalytic activity of calcium, while the pretreatment temperatures had little effect on the catalytic activity of iron. Both calcium and iron promoted the NO-char reaction, but the catalytic activity of the latter was higher than that of the former. NO reduction by CO was strongly promoted by Fe and Ca. The addition of O₂ in the char-NO-Ca or char-NO-Fe system promoted the NO reduction significantly. Oxidation/reduction mechanisms were proposed for the NO reduction by char catalyzed by Ca and Fe.